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The objective of this study was to investigate the mechanisms of cadmium (Cd) sorption on biochars produced at different temperature (300–600 °C) and their quantitative contribution. The sorption isotherms and kinetics of Cd^2 + sorption on biochars were determined and fitted to different models. The Cd^2 + sorption data could be well described by a simple Langmuir model, and the pseudo second order kinetic model best fitted the kinetic data. The maximum sorption capacity (Q_m) obtained from the Langmuir model for CIB500 was 188.8 mg g^− 1, which was greater than that of biochars produced at other temperature. Precipitation with minerals, ion exchange, complexation with surface oxygen-containing functional groups, and coordination with π electrons were the possible mechanisms of Cd^2 + sorption on the biochars. The contribution of each mechanism varied with the pyrolysis temperature. With increasing …